Hydrologic Imaging of Fractured Rock

1994 ◽  
Vol 353 ◽  
Author(s):  
Kenzi Karasaki ◽  
Andrew Cohen ◽  
Paul Cook ◽  
Barry Freifeld ◽  
Ken Grossenbacher ◽  
...  
Keyword(s):  
Rock Mass ◽  
High Resolution ◽  
Seismic Tomography ◽  
Pressure Transducer ◽  
Fractured Rock ◽  
Geophysical Data ◽  
Pressure Measurements ◽  
Transient Pressure ◽  
Fractured Rock Mass ◽  
Hydrologic Connections

AbstractVarious geophysical and hydrologic tests were conducted in a cluster of nine wells to image the hydrologic connections of a fractured rock mass. Results of intra-borehole flow surveys and cross-hole radar and seismic tomography surveys correlated very well, and indicated that there is a major feature at a depth of 30m. Systematic injection tests were conducted in all nine wells. Three to four intervals in each well were isolated using pneumatic packers. Each interval was equipped with a high resolution pressure transducer. Some 130 injection tests were conducted, and more than 4,100 cross-hole transient pressure measurements were obtained. A computer algorithm was developed to analyze such massive interference data systematically. As a result of the analysis, an image of the fracture connections emerged which is consistent with the geophysical data.

Study of the geometrical size effect of a fractured rock mass based on the modified blockiness evaluation method

2018 ◽  
Vol 11 (11) ◽  
Author(s):  
Qingfa Chen ◽  
Tingchang Yin ◽  
Wenjing Niu ◽  
Wenshi Zheng ◽  
Junguang Liu
Keyword(s):  
Rock Mass ◽  
Size Effect ◽  
Evaluation Method ◽  
Fractured Rock ◽  
Fractured Rock Mass ◽  
Geometrical Size

Application of Borehole Camera Technology in Fractured Rock Mass Investigation of a Submarine Tunnel

2019 ◽  
Vol 83 (sp1) ◽  
pp. 609 ◽  
Author(s):  
Zengqiang Han ◽  
Chuanying Wang ◽  
Sheng Hu ◽  
Yiteng Wang
Keyword(s):  
Rock Mass ◽  
Fractured Rock ◽  
Fractured Rock Mass ◽  
Borehole Camera

scholarly journals A methodology of re-generating a representative element volume of fractured rock mass

2020 ◽  
Vol 71 (4) ◽  
pp. 347-358
Author(s):  
DANG Hong-Lam ◽  
THINH Phi Hong
Keyword(s):  
Rock Mass ◽  
Fractured Rock ◽  
Fracture Network ◽  
Hydraulic Calculation ◽  
Fractured Rock Mass ◽  
Fracture Characteristics ◽  
Mechanical Calculation ◽  
Representative Element ◽  
Representative Element Volume ◽  
Actual Fracture

In simulation of fractured rock mass such as mechanical calculation, hydraulic calculation or coupled hydro-mechanical calculation, the representative element volume of fractured rock mass in the simulating code is very important and give the success of simulation works. The difficulties of how to make a representative element volume are come from the numerous fractures distributed in different orientation, length, location of the actual fracture network. Based on study of fracture characteristics of some fractured sites in the world, the paper presented some main items concerning to the fracture properties. A methodology of re-generating a representative element volume of fractured rock mass by DEAL.II code was presented in this paper. Finally, some applications were introduced to highlight the performance as well as efficiency of this methodology.

scholarly journals Numerical Analysis of the Mud Inflow Model of Fractured Rock Mass Based on Particle Flow

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Yongjian Pan ◽  
Huajun Wang ◽  
Yanlin Zhao ◽  
Qiang Liu ◽  
Shilin Luo
Keyword(s):  
Rock Mass ◽  
Pressure Gradient ◽  
Flow Direction ◽  
Fractured Rock ◽  
Water Pressure ◽  
Water Inrush ◽  
Quadratic Function ◽  
Particle Flow ◽  
Fractured Rock Mass ◽  
Particle Flows

Water inrush and mud outburst are one of the crucial engineering disasters commonly encountered during the construction of many railways and tunnels in karst areas. In this paper, based on fluid dynamics theory and discrete element method, we established a fractured rock mass mud inflow model using particle flow PFC3D numerical software, simulated the whole process of fractured rock mass mud inflow, and discussed the effect of particle size and flow velocity on the change of pressure gradient. The numerical simulation results show that the movement of particles at the corner of the wall when the water pressure is first applied occurs similar to the vortex phenomenon, with the running time increases, the flow direction of particles changes, the vortex phenomenon disappears, and the flow direction of particles at the corner points to the fracture; in the initial stage, the slope of the particle flows rate curves increases in time, and the quadratic function is used for fitting. After the percolation velocity of particles reaches stability, the slope of the curve remains constant, and the primary function is used for fitting; the particle flow rate and pressure gradient are influenced by a variety of factors, and they approximately satisfy the exponential function of an “S” curve.

Sign in / Sign up

Export Citation Format

Share Document